The fatigue material don't work in twonodelink elements

[TOKYOTech]

Hi guys,
I'm using a pair of twonodelink element to simulate a wood shear wall. I use the Fatigue material but it always failed at the first step, giving "material tag 3 failed from excessive strain", no matter how I set the maxstrain. By the way, the father material is SAWSMaterial. If I use the SAWSMaterial only, it works well. I read the source code of Fatigue from the svn,the following condition is the only part will give that warning:

if (trialStrain >= maxStrain || trialStrain <= minStrain) {
Cfailed = true;
opserr << "MFatigueMaterial: material tag " << this->getTag() << " failed from excessive strain\n";
DI = Dmax;
DL = Dmax;
return 0;
}
The strain of my element in first step is about 150, it is much smaller the default maxStrain 1e16. So please help me about that, thank you very much!

Following is my code:

wipe
puts "system"
model basic -ndm 3 -ndf 6
puts "node"
set h 0.91;
set s 1.82;
set l 1.21;
set h2 [expr $h*2];
set h3 [expr $h*3];
set s2 [expr $s*2];
set s3 [expr $s*3];
set l2 [expr $l*2];
set l3 [expr $l*3];
node 1 0 0 0
node 2 $s 0 0
node 3 $s 0 $h
node 4 $s 0 $h
node 17 0 0 $h
node 18 0 0 $h
puts "restrain"
fix 1 1 1 1 0 0 0;
fix 2 1 1 1 0 0 0;
puts "transf"
geomTransf Linear 1 1 0 0;
geomTransf Linear 2 0 0 1;
geomTransf Linear 3 0 0 1;
puts "element-beam&column"
set AC [expr 0.06*0.06];
set AB [expr 0.06*0.15];
set E 9500.0e10;
set G 1.5e10;
set JC [expr 0.141*0.06*pow(0.06,3)];# the torsional moment of the section
set JB [expr 0.249*0.15*pow(0.06,3)];
set Iyc [expr pow(0.06,4)/12];
set Izc [expr pow(0.06,4)/12];
set Iyb [expr 0.6*pow(0.15,3)/12]; #the second moment
set Izb [expr 0.15*pow(0.06,3)/12];
#element elasticBeamColumn $eleTag $iNode $jNode $A $E $G $J $Iy $Iz $transfTag
element elasticBeamColumn 1 1 18 $AC $E $G $JC $Iyc $Izc 1
element elasticBeamColumn 2 2 3 $AC $E $G $JC $Iyc $Izc 1
element elasticBeamColumn 3 17 4 $AC $E $G $JC $Iyb $Izb 2
puts "beam&column joint"


uniaxialMaterial ElasticMultiLinear 1 -strain [expr -0.03/$h] [expr -0.005/$h] 0.0 [expr 0.005/$h] [expr 0.03/$h] -stress [expr -1275.0/4] [expr -1025.0/4] 0.0 [expr 1025.0/4] [expr 1275.0/4];
uniaxialMaterial Elastic 9 1.0

element zeroLength 16 18 17 -mat 9 9 9 -dir 4 5 6
element zeroLength 17 3 4 -mat 9 9 9 -dir 4 5 6
puts "spring"
#K0-K5 follow the Fig 2.17 on page 39 of paper02 units N,M,Pa
#for shearwall
set F0 6000.5; #N
set F1 475.0
set S0 1181.4e3;#N/m
set S1 6.7e3
set S2 150.0e3
set S3 1008.2e3
set S4 15.0e3
set DU 0.100; #m
set alpha 0.6
set beta 1.1
set gama 1.2
set delta 0.8
#R0-R4 follow the fig of opensees SAWS guide
set R1 [expr $S1/$S0]
set R2 [expr -$S2/$S0]
set R3 [expr $S3/$S0]
set R4 [expr $S4/$S0]
# the shearwall parameters need to be turned into element parameters
set p1 [expr (pow($s,2)+pow($h,2))/(2*pow($s,2))];
set coss [expr $s/(sqrt(pow($s,2)+pow($h,2)))];
set sins [expr $h/(sqrt(pow($s,2)+pow($h,2)))];
set p2 [expr 1/(2*$coss)];
set sF0 [expr $p2*$F0];
set sF1 [expr $p2*$F1];
set sDU [expr $coss*$DU];
set sS0 [expr $p1*$S0];
uniaxialMaterial SAWSMaterial 2 $sF0 $sF1 $sDU $sS0 $R1 $R2 $R3 $R4 $alpha $beta $gama $delta;
#uniaxialMaterial Fatigue $matTag $tag <-dmax $dmax> <-E0 $E0> <-m $m> <-min $min> <-max $max>
uniaxialMaterial Fatigue 3 2 -min -50000 -max 50000

element twoNodeLink 38 17 2 -mat 3 9 9 9 9 9 -dir 1 2 3 4 5 6 -orient $coss 0 -$sins 0 1 0
element twoNodeLink 39 1 4 -mat 3 9 9 9 9 9 -dir 1 2 3 4 5 6 -orient $coss 0 $sins 0 1 0

puts "equal dof"
equalDOF 17 18 1 2 3
equalDOF 4 3 1 2 3

puts "recoeder"
recorder Node -file node4_disp.out -time -node 4 -dof 1 disp;
recorder Element -file ele38_f.out -time -ele 38 force;
recorder Element -file ele38_s.out -time -ele 38 strains;
recorder Element -file Damage.out -time -ele 38 material 3 damage

puts "load"
pattern Plain 1 Linear {
load 17 1 0 0 0 0 0
}
puts "analysis"
constraints Transformation
numberer Plain
system BandGeneral
test EnergyIncr 1.0e-6 100
algorithm Newton
analysis Static
integrator DisplacementControl 17 1 0.0001
analyze 5
integrator DisplacementControl 17 1 -0.0001
analyze 10
integrator DisplacementControl 17 1 0.0001
analyze 15
integrator DisplacementControl 17 1 -0.0001
analyze 20
integrator DisplacementControl 17 1 0.0001
analyze 25

[zhanandong]

Hello,I am a student researching wood frame shear wall,and I am so interesting in your research.In your modeling,I can't find any board,did you use two “element twoNodeLink” to simulate board?

[zhanandong]

Sorry,I don't know where your model is wrong,but I still want to talk to you about your research.Did you use nails to connect beam ,column and shearwall?
My email is "1363576665@qq.com",I really hope you can answer my questions.